1. Field of the Invention
The present invention relates to an internal combustion engine automatic-stop/restart control system that automatically stops an engine (referred to as an internal combustion engine, hereinafter) when an automatic stopping condition is satisfied and then restarts the internal combustion engine when a restarting condition is satisfied.
2. Description of the Related Art
In recent years, for the purpose of improving the gasoline mileage of a motor vehicle and reducing an environmental load, there has been developed an internal combustion engine automatic-stop/restart system that automatically cut off the supply of fuel so as to automatically stop an internal combustion engine, when the operation by a driver satisfies a predetermined condition (e.g., brake-pedal stepping-on operation while the vehicle travels at a speed lower than a predetermined speed) for stopping the internal combustion engine, and then restarts fuel injection so as to automatically restart the internal combustion engine, when the operation by the driver satisfies a predetermined condition (e.g., brake-pedal releasing operation, accelerator stepping-on operation, or the like) for restarting the internal combustion engine.
In this internal combustion engine automatic-stop/restart system, the internal combustion engine performs fuel injection and ignition control in accordance with a crank angle. By being configured in such a way as to generate a crank angle signal pulse every predetermined crank angle as the internal combustion engine rotates, by means of a crank angle sensor for detecting the crank angle of the internal combustion engine, and to generate a cylinder determination signal pulse at a specific crank angle, the internal combustion engine automatic-stop/restart control system knows the crank angle. In general, there are formed teeth-missing portions where outer-circumference teeth of the signal rotor of a rotation sensor are missing, and by utilizing, as a reference signal, an unevenly-spaced pulse generated at the teeth-missing portions, cylinder determination is performed.
In such an internal combustion engine automatic-stop/restart control system as described above, after an idling stop, preparation is made for internal combustion engine restart request while the internal combustion engine inertially rotates; when the internal combustion engine rotation speed becomes the same as or lower than a predetermined rotation speed, the coupling between the pinion gear and the ring gear is started without rotating the starter motor; and at a time point when the motor rotation speed (equal to the pinion gear rotation speed, in this case; the same applies hereinafter) and the internal combustion engine rotation speed synchronize with each other, the coupling between the pinion gear and the ring gear is completed. There has been proposed a system (e.g., refer to Patent Document 1) in which when after the completion of the coupling between the pinion gear and the ring gear, the restart request is issued, the starter motor is energized and the starter motor drives the internal combustion engine so that the restart of the internal combustion engine is completed.